Cyclohexyl unsymmetrical diphenyl ethanes



' metrical diphenyl ethanes.

' Patented June 1941 crcnona'xrr.

Frank B. Smith and. na m'w.

The

Mich, assignora to unsnmmmcar. nrrnam arms Moll, 'Midland, I DowChemical Company, Midland, Mich., a corporation of Mich- No Drawing.Application January is, 1939, Serial No. 251,126

5 Claims. ((51. 260-868) The reaction is preferably carried out by heat-This invention concernscertainnew chemical,

products prepared by reaction between unsymmetrical diphenylethane andcyclohexene or other cyclohexylating agent. The new products comprisemixtures or unsymmetrical diphenyl ethane derivatives wherein theunsymmetrical 'diphenyl ethane is substituted in one orboth of the arylnuclei by one or more cyclohexyl groups. They vary in physicalcharacteristics from colorless liquids to resinous solids, dependingupon the number of cyclohexyl groups in the molecule. They areparticularly useiulas plasticizing or addition agents for varioussynthetic plastic compositions and may also be employed as liquiddielectric agents and as intermediates in the preparation of othernew-chemical products.

The new cyclohexylunsynmietrical diphenyl ethane products are preferablyprepared by reacting cyclohexene with unsymmetrical diphenyl ethane inthe presenceoi an alkylation catalyst, e. g. aluminum chloride,ferricchloride, boron trifluoride, aluminum bromide, activated bleachingearths, such as Retrol or Tonsil, etc. desired, however,

such as cyclohexyl cyclohexanol, etc., actants may be employed in anydesired proportions', although the products vary in' propertieschloride, cyclohexyl bromide,

with changes in such proportions. For'example,

unsymmetrical diphenyl ethane-may be reacted may be employed. The reing.amixture of the reactants and. catalyst under pressure in a closedvessel or autoclave, al-

though it may, if desired, be carried-out at atmospheric pressure bygradually adding thecyclohexylating agent to a heated and well-stirredmixture of unsymmetrical diphenyl ethane and catalyst, and thereaftercontinuing the heating and stirring until reaction is complete. Whenoperating at atmospheric pressure, however, the reaction takes placeslowly, particularly when a molecular excess of the cyclohex'ylatingagent is used, and for this reason we prefer to carry out the reactionunder increased pressure. The reaction temperature is usually betweenabout 150 C. and about 250 0., although higher temperatures maysometimes be employed, especially, when preparing thepoly-cyclohexylated compounds. The reaction, is usually complete in from1 to 10 hours depending upon the proportion of reactants and the"reaction conditions employed. Upon completion-of the reaction, the

If other cyclohexylating agents,

with its molecular equivalent of cyclohexene or] other cyclohexylatingagent to produce a mixture comprising isomeric mono-cyclohexylunsymmetrical diphenyl ethanes together with some dicyclohexyl and otherpoly-cyclohexyl unsyrmq The yield of polycyclohexyl products may beraised by increasing mixture is treated to remove the catalyst, and

any unreacted unsymmetrical diphenyl ethane and cyclohexylating agent isdistilled on under vacuum. The cyclohexyl unsymmetrical diphenyl ethaneproduct may be employed directly as a plasticizin'g agent, intermediate,etc'., 'orv it may be fractionally distilled-to obtain fractionsrepresenting mixed isomeric mono-cyclohexyl unsymmetrical diphenylethanes, mixed isomeric ,di-cyclohexyl unsymmetrical diphenyl ethanes.

etc

which the principle of the invention has been applied, but is not to beconstrued as limiting the the proportion 01' the cyclohexylating agentemployed in the reaction or' by cycloh'xylatlng the mono-cyclohexylcompounds obtained from a previous reaction. Ordinarily, we prefer toemploy approximately 1-4 moles of the cyclohexylating .agent per mole ofunsymmetrical diphenyl ethane. The optimum proportion of catalyst variessomewhat with the particular reactants employed and the conditions underwhich the reaction is carried out, but we usually employ between about0.01 and 0.15 ,part by weight of catalyst per part 01 unsymmetricaldiphenyl ethane.

j Example A mixture of 364 gra ms (2.0 moles) of .unsymmetrical diphenylethane and 18 grams of Retrol was heated at 200 C. to drive oil. theresidual water contained in the Retro], after which 180.0

grams (2.2 'moles) of cyclohexene was added gradually with stirringwhile maintaining the mixture at approximately 200 C. The reactionproceeded quite slowly, however, and after two hours heating thepartially reacted mixture was cooled and charged into a.pressure vesselto-' g'etherswith an additional 364 grams of unsymmetrical diphenylethane, 210 grams of cyclo- The following example illustrates one way inI hexene, and 82 grams of dried Retrol. The mixture was then heated at200-220 C. for one hour under the autogenicpressure of the reactants.Upon completion of the reaction, the mixture was-cooled to 150 C. andfiltered to remove the catalyst. The crude cyclohexyl unsymmetricaldiphenyl ethane product was a dark golden yellow liquid displaying agreen fluorescence.

was iractionally distilled under vacuum, whereby ethanes, said mixturebeing prepared by reacting unsymmetrical diphenyl .ethane with. acyclohexylatingagent in the presence an alkylation catalyst.

3. A mixture consisting substantially of isomeric nuclearlymono-cyclohexylated and nuclearly di-cyclohexylated unsymmetricaldiphenyl ethanes, said mixture being a colorless viscous liquiddistilling at temperatures between about In the following claims theterm cyclohexyl unsymmetrical diphenyl ethanes" is employed as a genericterm to include unsymmetrical diphenyl ethanes in which either or bothof the aryl nuclei hear at least one cyclohexyl substituent.

Other modes of applying the principle of our invention may be employedinstead of those explained, change being made as regards the methodherein disclosed or the. materials employed provided the product statedby any of the following claims or the equivalents of such statedproducts may be obtained.

We therefore particularly point out and distinctly claim as ourinvention:' 1. A nuclearly cyclohexylated unsymmetrical diphenyl ethane.

2. A- mixture consisting substantially. of nuclearly mono-cyclohexylatedand nuclea'rly poly-cyclohexylated unsymmetrical diphenyl tmcyclohexylated the iollowingiractions were obtained: I 237 C. and about250 C. under 20 millimeters Table r u I n it in m "ass sfif" ams Y .5 mm

- pressure Gram I 1 Colors? mobile 292 Upto155 Unreacied materials.

2 Colorless liquid 83 155-212..' 0.067 1.5440 Mfixed traction. 3 do 129212-237 0. 993 1.5578 isomeric mono-cyclche lunsymmneg etrical diphenyetha 4 Colorless viscous 155 237-250 0.998 1. 5623 Mixed isomericmonound diliquid. clo-hexyl unsymmetrical dipbenyle es. r 5 Light yellowvis- 139 250-300 l.000. 1.6599 isomeric dl-eyclohcxyl urn-- coilsliquid. symmetrical diphenyl ethanec. 6 Very viscous am- 74 300-300under 1.006 at (SO/60 C..- l. 5001 Mixed isomeric diand trior herliquid. 2mm. clo-hexyl unsymmetrical i- Bilbenyl ethanes. Residue.. Darkamber rcsm. 100 Above 300 unixcd poly-cyclohexyl unsymder 2 mm, metricaldiphenyl ethanes.

pressure, and having a specific gravity of ap proximately 0.998 at 25l25C.

4 A mixture consisting substantially of isomeric nuclearly.di-cyclohexylated unsymmetrical diphenyl ethanes, said yellow viscousliquid distilline at temperatures between about 250C. and about 300 C.under millimeters pressure, and having a 5, A mixture consistingsubstantially of isomeric nuclearly di-cyclohexylated and nuclearlyunsymmetrical ethanes, said liquid mixture being a viscous amber liquiddistilling at temperature between about 300 C. under 20 millimetersabout 300 C. under 2 millimeters pressure, and having a specific gravityof approximately 1.006 at 60/60 C.

- FRANK B. BMITIL- nnnom w. Mom.

mixture being a light specific gravity or approximately 1.000 at /25" 0.

diphenyl.

pressure and

